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Continuous stiffness measurement (CSM) and dynamic contact module (DCM) nanoindentation measurements were used to characterize the mechanical properties of plasma‐polymerized tetravinylsilane films deposited by PECVD at RF powers ranging from 10 to 70 W. The Young's modulus and hardness as a function of the indenter displacement (5–500 nm) were investigated for films of 1‐µm thickness. The Young's modulus (hardness) was observed to increase from 8.3 (0.9 GPa) to 58 GPa (9.5 GPa) with enhanced RF power. Nanoindentation analysis together with AFM imaging revealed a grain character of films deposited at a higher power. Finite element analysis was used to simulate nanoindentation measurements and evaluate properties of the elastic–plastic material.

Poly(3-hydroxybutyrate) (PHB) has been shown to be efficiently nucleated by exfoliated graphite nanoplatelets (xGnP). The nucleating effect of xGnP was investigated using differential scanning calorimetry, optical microscopy and atomic force microscopy. Nonisothermal crystallization of PHB from the melt required lower activation energies for PHB containing 1 wt % and 3 wt % xGnP (À214 and À102 kJ/mol respectively) than for pure PHB (À60 kJ/mol). A kinetic study of the PHB/xGnP crystallization employing a modified form of the Avrami equation revealed that the presence of xGnP increased the PHB crystallization temperature, as well as the crystallization rates, and generated smaller and more numerous spherulites. Optical microscopy and atomic force microscopy confirmed the incorporation of xGnP into the lamellar structure of the PHB spherulites and provided insight into the influence of xGnP on spherulite size and lamellae thickness.

Cholesterol crystals damaged the endothelium and reduced vasodilator response, potentially aggravating myocardial ischemia after interventions.

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